Form 5 revision: Structure of atom (Form 4 chapter 2)

What is the process occurs when iodine is heated?

(a)  

The graph shows ____________________________.

• supercooling curve

• heating curve

• cooling curve

This graph will occur when _______________.

• the substance is not cooled evenly

• the substance is hard

• the substance has a low melting point than the room temperature

• the substance has a high melting point

Which of the following is true?

• Liquid particles absorb heat and turn into solid

• Gas molecules contain more kinetic energy than liquid molecules

• Solid has lower force of attraction between molecules than liquid

• The process to turn liquid to gas is condensation

Rate of diffusion can be increased by ___________________

• decreasing the temperature

• increasing the temperature

• having a lower molecular mass

• having a higher molecular mass

Which of the following has the highest rate of diffusion?

• ammonia

• hydrogen chloride

• methane

• carbon dioxide

during the melting process, the substance exist in ________________.

• solid

• solid and liquid

• liquid

• liquid and gas

Which two substances have the same number of valence electrons?

Proton number of A: 8

Proton number of Z: 6

Proton number of D: 16

Proton number of X: 11

• A and Z

• Z and D

• A and D

• Z and X

The nucleon number of element A is 20. It contains 9 protons. What is the number of electron?

• 20

• 11

• 9

• 10

Who discovered proton?

• J,J,Thompson

• James Chadwick

• Ernest Rutherford

• Neils Bohr